It would seem that in this version, the songs 'last modification date' gets updated without me changing anything on the song. Just displaying the song seems to trigger the modification to the date.
i noticed this because in the songs tab, I use 'order by last change date'.

I did some further testing and it would seem, the issue is already present in MSP 2.1.9.

It would also seem only a limited number of songs are affected. Their date changes every time I view them. Other songs are ok.... strange ...
So far I have not been able to notice anything special about the affected songs that sets them apart from the rest ...